package com.zl.task.config;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTDecodeException;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.zl.task.dto.UserDTO;
import com.zl.task.pojo.ServiceEnterprised;
import com.zl.task.pojo.ServiceMechanism;
import com.zl.task.service.IServiceEnterprisedService;
import com.zl.task.service.IServiceMechanismService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;

import static com.zl.task.commom.ServiceCode.ENTERPRISE_TYPE;
import static com.zl.task.commom.ServiceCode.MECHANISM_TYPE;

/**
 * 拦截器
 * @author YinlinGeng
 */
public class AuthenticationInterceptor implements HandlerInterceptor {
    @Autowired
    private IServiceMechanismService mechanismService;
    @Autowired
    private IServiceEnterprisedService enterpriseService;

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
        // 从 http 请求头中取出 token
        String token = httpServletRequest.getHeader("token");
        // 从http 请求头中取出 用户类型 type
        String type = httpServletRequest.getHeader("type");
        // 如果不是映射到方法直接通过
        if(!(object instanceof HandlerMethod)){
            return true;
        }
        HandlerMethod handlerMethod=(HandlerMethod)object;
        Method method=handlerMethod.getMethod();
        //检查是否有passtoken注释，有则跳过认证
        if (method.isAnnotationPresent(PassToken.class)) {
            PassToken passToken = method.getAnnotation(PassToken.class);
            if (passToken.required()) {
                return true;
            }
        }
        //检查有没有需要用户权限的注解
        if (method.isAnnotationPresent(UserLoginToken.class)) {
            UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
            if (userLoginToken.required()) {
                // 执行认证
                if (token == null) {
                    throw new RuntimeException("无token，请重新登录");
                }
                // 获取 token 中的 user id
                String userId;
                try {
                    userId = JWT.decode(token).getAudience().get(0);
                } catch (JWTDecodeException j) {
                    throw new RuntimeException("401");
                }

                UserDTO userDTO = new UserDTO();
                if (ENTERPRISE_TYPE.equals(type)) {
                    ServiceEnterprised enterpriseById = enterpriseService.getEnterprisedById(userId);
                    userDTO.setId(enterpriseById.getEnterprisedId().toString());
                    userDTO.setUserName(enterpriseById.getEnterpriseName());
                    userDTO.setPassword(enterpriseById.getEnterprisePassword());
                }else if (MECHANISM_TYPE.equals(type)){
                    ServiceMechanism mechanismById = mechanismService.getMenchanismById(userId);
                    System.out.println(mechanismById);
                    userDTO.setId(mechanismById.getMechanismId().toString());
                    userDTO.setUserName(mechanismById.getMechanismName());
                    userDTO.setPassword(mechanismById.getMechanismPassword());
                }else{
                    throw new RuntimeException("用户不存在，请重新登录");
                }

//                if (userDTO == null) {
//                    throw new RuntimeException("用户不存在，请重新登录");
//                }
                // 验证 token
                JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(userDTO.getPassword())).build();
                try {
                    jwtVerifier.verify(token);
                } catch (JWTVerificationException e) {
                    throw new RuntimeException("401");
                }
                return true;
            }
        }
        return true;
    }


    @Override
    public void postHandle(HttpServletRequest httpServletRequest,
                           HttpServletResponse httpServletResponse,
                           Object o, ModelAndView modelAndView) throws Exception {

    }
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest,
                                HttpServletResponse httpServletResponse,
                                Object o, Exception e) throws Exception {
    }
}
